Brake



Feb. 17, 1931. R. s. SANFORD BRAKE Original Filed Aug. 1. 1925 INVENTOR.01 '5: San (1 BY I W ATTOR EY.

Patented Feb. 17, 1931 UNITED STATES PATENT OFFICE BOY S. SANFORD,OFSOUTH BEND, INDIANA, ASSIGNOR TO BENDIX BRAKE COMPANY, OF SOUTH BEND,INDIANA, A CORPORATION OF ILLINOIS BRAKE Original application filedAugust 1, 1925, Serial No. 47,452. Divided and this application filedAugust 26, 1929. Serial No. 388,348. I

This invention relates to brakes and is illustrated as embodied in aninternal expandtapers in its web portion to provide for progressivevariation in its flexibility, the anchoring of the friction device beingeffected by a pair of diverging anchor links pivoted to each other andto the band.

The above and other features of the invention, including various novelcombinations of parts and desirable particular constructions, will beapparent from the following description of the illustrative embodimentshown in the accompanying drawing, in which:

Figure 1 is a vertical section just inside the wheel through my novelbrake;

Figure 2 is a section taken on the line 22 through the novel anchoringlink of the brake.

As disclosed inthe figures of the drawing, the friction means preferablyincludes a double wrapping band 10, the same being arranged between thedrum 14- and the backing plate 16, which band is adapted to be ex-'panded to apply the brake by means shown as a double cam 18.

The band 10 is preferably provided with a reinforcing web 20,comparatively heavy at its ends, which web tapers gradually toward itscenter, as clearly disclosed in Figure 1, thus giving the desiredprogressive smooth action of the brake. A return spring 22 secured tothe ends of the web adjacent the applying means holds the ends of theband against the applying means.

The aforementioned structure is more completely described in myco-pending application No. 47,452. filed August 1, 1925, the instantapplication being a division thereof. The novelty of' this case isparticularly d1- rected to the means for anchoring the friction bandirrespective of the direction of drum rotation. that is, with the carmovingelther forward or backward. As clearly disclosed in the figures ofthe drawing, this anchoring means preferably comprises a pair of links23 and 24, each link comprising two parallel stampings, as disclosed inFigure 2, the four stampings of both links pivoted to the band by apivot pin 26 preferably at a point in the band intermediate the rigidand most flexible portions thereof, said links diverging therefromtoefi'ect the function hereinafter'described. The parts of each link areprovided with slots 28 embracing anchor pins 30 and 31 carried by thebacking plate 16. A spring 32 normally holds the band and both sets oflinks in idle position with the brake off and it will be further seenthat said spring 32 serves to hold the links or their equivalent againstthe anchor pins 30 and 31 during the first stage of-applying thebrake,.that is while the ends of the band are being spread apart againstthe drum. Upon completion of the application of the brake, if the drumis turning clockwise, the link 24 leaves its anchor 30,

, while the torque of the entire band is trans mitted to the otheranchor 31 by the link 23, whereas if the drum is turningcounterclockwise the link 23 draws away from itsanchorage and the anchor30 takes the torque of the entire band.

A very competent and effective brake is thus presented, having atwo-thirds wrap in one direction of drum rotation and. a onethird wrapin the other. With the brake efdirection of drum rotation, as indicatedin Figure 1, there is provided a rigid reinforced servo section of theband which serves to effectively thrust the more flexible portion of theband into drum engagement. The same is true to a lesser extent of theremaining portion of the band with the drum turning inv acounterclockwise direction.

While but one embodiment of the invention has been disclosed anddescribed in detail, it is not my intention to limit the inventionthereto but only so far as maybe embraced by the scope of the appendedclaims.

I claim:

1. A brake comprising, in combination, a drum, a brake band within thedrum extending substantially the entire circumference thereof andtapered to be of progressively varying flexibility, and a pair of lostmotion links arranged to take the braking torque and offset from thecentral portion of the band and engaging the same side of the band wherethe most flexible portion merges into a comparatively nonflexibleportion, one of said links being efi'ective when the drum is turning inone direction and the other being eflective when the drum is turning inthe other direction. v

2. A brake comprising, in combination, a drum, a brake band within thedrum extending substantially the entire circumference of the drum, and apair of lost motion links arranged to take the braking torque and offsetfrom the central portion of the band and engaging at least one side ofthe band, said links being pivoted tosaid band by a common pivot ,pin,one of'said links being effective when the drum is turning in onedirection and the other being effective when the drum is turning in theother direction.

3. A brake comprising, in combination, a drum, a brake band within thedrum extending substantially the entire circumference thereof. a pair oflost motion links arranged to take the braking torque and offset fromthe central portion of the band and engaging the same side thereofimmediately adjacent said central portion, one of said links beingeffective when the drum is turning in one direction and the other beingeffective when the drum is turning in the other direction.

4. A brake comprising, in combination, a drum, a brake band within saiddrum, a pair of lost motion links arranged to take the braking torque,said links being pivoted to a portion of the band offset from thecentral portion thereof, said links diverging one from another and beingalternately efiective, depending upon the direction of drum rotation, totake the braking torque.

5. A brake comprising, in combination, a drum, a brake band within thedrum extending substantially the entire circumference thereof, a pair oflost motion links arranged to take the braking torque and offset fromthe central portion of the band and engaging at least one side of theband, said links being pivoted to said band by a common pivot pin andslotted at their ends to surround a fixed anchor post, one of said linksbeing effective when the drum is turning in one direction and the otherbeing eifective, when the drum is turning in the other direction, totake th braking torque.

In testimony whereof I have hereunto signed my name.

ROY S. SANFORD.

